It sounds suspiciously like there's been some serious personal growth with her. That's great news. It also sounds like she's gone from the young adult stage of taking family for granted and expecting love and generosity without giving any, to actually understanding that a family who loves you is a gift, and it's so much better when the love flows both ways. I think you may have reached the magical mother heaven of "being appreciated".
And the best of all mother joys- a loving relationship with a healthly adult child.
I'm really happy for you. I hope things only get better from here.